// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
// Distributed under the MIT License (http://opensource.org/licenses/MIT)

#pragma once

#include <spdlog/details/file_helper.h>
#include <spdlog/details/null_mutex.h>
#include <spdlog/details/synchronous_factory.h>
#include <spdlog/sinks/base_sink.h>

#include <chrono>
#include <mutex>
#include <string>

namespace spdlog {
namespace sinks {

    //
    // Rotating file sink based on size
    //
    template <typename Mutex> class rotating_file_sink final : public base_sink<Mutex>
    {
    public:
        rotating_file_sink(filename_t base_filename,
                           std::size_t max_size,
                           std::size_t max_files,
                           bool rotate_on_open = false,
                           const file_event_handlers& event_handlers = {});
        static filename_t calc_filename(const filename_t& filename, std::size_t index);
        filename_t filename();

    protected:
        void sink_it_(const details::log_msg& msg) override;
        void flush_() override;

    private:
        // Rotate files:
        // log.txt -> log.1.txt
        // log.1.txt -> log.2.txt
        // log.2.txt -> log.3.txt
        // log.3.txt -> delete
        void rotate_();

        // delete the target if exists, and rename the src file  to target
        // return true on success, false otherwise.
        bool rename_file_(const filename_t& src_filename, const filename_t& target_filename);

        filename_t base_filename_;
        std::size_t max_size_;
        std::size_t max_files_;
        std::size_t current_size_;
        details::file_helper file_helper_;
    };

    using rotating_file_sink_mt = rotating_file_sink<std::mutex>;
    using rotating_file_sink_st = rotating_file_sink<details::null_mutex>;

}  // namespace sinks

//
// factory functions
//

template <typename Factory = spdlog::synchronous_factory>
inline std::shared_ptr<logger> rotating_logger_mt(const std::string& logger_name,
                                                  const filename_t& filename,
                                                  size_t max_file_size,
                                                  size_t max_files,
                                                  bool rotate_on_open = false,
                                                  const file_event_handlers& event_handlers = {})
{
    return Factory::template create<sinks::rotating_file_sink_mt>(logger_name, filename, max_file_size, max_files, rotate_on_open, event_handlers);
}

template <typename Factory = spdlog::synchronous_factory>
inline std::shared_ptr<logger> rotating_logger_st(const std::string& logger_name,
                                                  const filename_t& filename,
                                                  size_t max_file_size,
                                                  size_t max_files,
                                                  bool rotate_on_open = false,
                                                  const file_event_handlers& event_handlers = {})
{
    return Factory::template create<sinks::rotating_file_sink_st>(logger_name, filename, max_file_size, max_files, rotate_on_open, event_handlers);
}
}  // namespace spdlog

#ifdef SPDLOG_HEADER_ONLY
#include "rotating_file_sink-inl.h"
#endif
